Kerr County, Texas, lacked a “last mile” warning mechanism that could have saved residents before the deadly floods devastated the area, including a children’s summer camp, killing more than 80 people.

An updated flash flood warning was released by the National Weather Service on Monday at 2:47 p.m. in effect until 5:45 p.m. for Chester County.

Catastrophic flooding struck central Texas on Friday as the Guadalupe River surged by more than 20 to 26 feet within 90 minutes, causing widespread devastation and forcing mass evacuations in Texas Hill Country. At least 80 people have been killed in the floods while others remain missing or displaced and more than 850 people required rescuing.